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NASA Greenlights Cargo Capsule Launch Monday

A SpaceX Falcon 9 rocket attached to the cargo-only capsule called Dragon lifts off from the launch pad on October 7, 2012 in Cape Canaveral, Florida. (Photo by Joe Raedle/Getty Images)

(Photo by Joe Raedle/Getty Images)

CAPE CANAVERAL (CBSMiami/AP) — NASA has given the go ahead for a supply ship to blast off Monday for the International Space Station.

Liftoff is scheduled for 4:58 p.m. from Cape Canaveral. The unmanned Dragon cargo capsule holds more than 2 tons of supplies and science experiments.

NASA decided Sunday to stick with the planned launch of the SpaceX ship, despite a critical computer outage at the space station.

“We’re good to go,” said NASA space station program manager Mike Suffredini.

Suffredini noted the many important supplies aboard the Dragon, including a new spacesuit and repair parts for the older spacesuits already in orbit. Much-needed food is also packed away.

“There’s a certain amount of urgency to go ahead and get these vehicles” at the space station, he told reporters. These shipments have to fit around other space station operations, like crew comings and goings.

“Things start to bunch up,” Suffredini said, “and so we’re just trying to fly as soon as we safely can, which is what we believe we’re doing.”

This backup computer, located on the outside of the space station, mysteriously failed to work when activated Friday. The main computer kept operating perfectly, and the six-man crew was never in any danger. NASA debated whether to delay the SpaceX mission and, on Sunday, determined the station has sufficient redundancy to safely support the visiting vessel.

A spacewalk will be required, meanwhile, to replace the bad computer. Engineers don’t know why it failed.

NASA rushed material for the computer replacement job to the Cape Canaveral launch site over the weekend, for packing into the Dragon. While not essential, the gasket-like item will make the task easier for the astronauts.

For the past few years, NASA has been paying SpaceX — Space Exploration Technologies Corp. — and Virginia-based Orbital Sciences Corp. to keep the station well stocked. The need arose after the space shuttles — NASA’s workhorses for station shipments — were retired in 2011. Russia, Europe and Japan also make occasional deliveries.

As soon as the Dragon soars, the space station’s solar panels will be moved into the proper position for its arrival, Suffredini said. That will guard against any complications resulting from additional computer breakdowns. Luckily, the sun’s angle is favorable right now for thermal conditions at the outpost, he noted.

More than a dozen of these computers, called MDMs or multiplexer-demultiplexers, are located on the exterior of the space station. This was the first one to fail outside; it’s been in place for more than a decade and was a backup for the thermal cooling system, solar-wing rotating joints, railcar for the robot arm, and other systems.